Please looks at California from the map.
As you most likely know, certain states are immediately called for candidates during elections - well before all the votes are counted in those states - because they know which party the state tends to vote for, as well as other factors like the precincts reporting and county demographics. It's where the notions of red state, blue state, and battleground (purple) state come from.
Do the Germans know this? Or do they just go by voting data they're receiving at the time? I'm not sure one way or another...
Regardless, we know California is a blue state as far as recent election history (as far back as Bush2 I think? I gotta check but it's been blue for a while)...this is a relative constant...but in your German map it's red. Meanwhile, every election map in the states projected it blue as soon as it started reporting.
In fact, I think a few more traditionally blue states are marked red in this map too, which is an aberration. This shows the German map is either (a) in error, or (b) incomplete at the time it was created.
You must remember that mail-in ballots are traditionally held to be counted later, while in-person ballots are traditionally counted first because in normal circumstances there are more in-person ballots.
But we're in a pandemic.
Remember Trump told his supporters not to trust mail-in ballots but to vote in person. This is why you have a red map initially. Most people who voted for trump voted in-person, and those ballots were counted first. Most people who voted for Biden voted by mail, which were counted after in-person votes as usual.
Most analysts and statisticians tried to warned Americans about "red and blue waves" weeks before the general election; publishing articles warning this is how the data would presented itself this cycle.
It's all due to the pandemic.